Alarm clock



FIG. 1 is a front and top-right perspective view of an alarm clock showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a right side elevational view thereof. 

The ornamental design for an alarm clock, as shown and described. 